166 CLASSIFICATION OF [CH. 
The very slender and long “seed” and caryopsis distinguish this 
from all but B. erectus, which has a shorter awn. Perhaps the awn 
is truly terminal: if so it should go with Festuca Myurus, &c. (see 
p- 171). The length varies greatly. 
Bromus giganteus, L. 
Palea 7 mm. long and inrolled, the base and rachilla 
bristly, indistinctly 5—7 nerved, the tip bifid: sub- 
terminal awn serrulate, 12—15 mm. long. 
Caryopsis 4°5 mm. long, flattened, thin, glabrous. 
The caryopsis is shorter and more ovoid than in other Bromes. 
== Palea expanded above (coracle-shaped), awn 
from sinus between two blunt or triangular 
teeth. 
Bromus arvensis. 
Bromus arvensis, var. mollis, L. (Fig. 73). 
Palea oblong or obovate, somewhat flattened above 
(coracle-shaped), distinctly 5—7 ribbed, 8—9 mm. long, 
not hairy, though the ribs may be ciliate. Awn smooth, 
arising from the depression between two teeth or rounded 
projections. Caryopsis flattened and thin, 6 x 15 mm.; 
apt to fall loose from the palee. 
In the variety B. secalinus the awn is usually shorter than the 
elliptical palea, and originates in the sinus of a notch (Fig. 74): in 
B. mollis from between two teeth, and is as long as the obovate palea. 
Bromus maximus and B. madritensis are both rare. 
The broader nerved paleze of B. mollis and shorter, fatter 
caryopsis, as well as the longer awn distinguish it from B. secalinus 
and B. arvensis. In the other Bromes the palea is more inrolled and 
the “seed” more slender as a rule. The rachilla is usually bent 
above into a slight kink. 
The Bromes are an extremely difficult group. The awn is 
inserted between the two teeth of the palea or just below. The 
palea smooth or ciliate on the nerves or roughly hairy. The fruit is 
